Exposure and Fate of Insecticides and Fungicides in Swiss Surface Waters

The exposure and fate of insecticides and fungicides from agricultural fields into surface waters has not been studied in much detail, neither internationally nor in Switzerland, compared to the work done on herbicides. However, mainly insecticides can already affect aquatic organisms at very low concentrations in surface waters.

The aim of this project is therefore to better understand the exposure and fate of insecticides and fungicides in Swiss surface waters. In a first step, a situation analysis was carried out, containing all insecticides and fungicides that are registered in Switzerland. Based on application patterns, sales statistics, degradation rates, polarities, and ecotoxicological data, the 40 most relevant insecticides, fungicides, and relevant metabolites were selected for further analysis.

In a field study done in cooperation with cantonal authorities (March to July 2012), water samples as well as passive samples were collected at 5 different locations. The sampling locations were selected based on size and different land uses and ranged over the whole Swiss midlands. The samples were analyzed by high-resolution mass spectrometry (LC-HRMS/MS) as well as by gas chromatography mass spectrometry (GC-MS/MS). This approach provides a representative picture of the contamination of insecticides and fungicides in Swiss surface waters.

Based on the analysis results, the most relevant substance classes are selected for a more detailed investigation on input pathways as well as ecotoxicological potentials.

Status: on-going

Funding: Federal Office for the Environment (FOEN)